Lifter roof



Feb. 13. 1945.

D. E. LARSON LIFTER'ROOF Filed Nov. 28, 1941 2 Sheets-Sheet l IKZJeW UK-jazzQiMjfaz 7607 Feb. 13, 1945.

Fzy 5 D. E. LARSON LIFTER'ROOF Filed Nov. 28, 1941 2 Sheets-Sheet 2 I Il Fave/(Z arp or more pointsand oiier almost no resistance of the roof.

LIFTER noon. Donald E liarsongfchicago, 111., assignorto Y 7 i cagoBridge ;& IronCompany.ac'orporationof 1 I Illinois Application Thisinvention relates to improvements in lifter roofs and more especiallysuch a device in con-' nection with a tank, shell or container adaptedfor the storage of gases, or volatile liquids.

Among the features of my invention is the proylsion of guiding meansforthe roof causing it to rotate as it rises and falls in 'much the samemanner as a lifter roof with spiral guiderailsi The means I employ,however, is much cheaper .and simpler in construction and operation thanthe employment of guide rails and has other advantages that will bepointed out hereinafter.-

In general my invention comprises a seriesyofslanting rocker armswiththeir lower endspiV-L oted to the tank and their upper ends to theroof ,so that it is more level as it moves upwardly and downwardly. Therocker armS, must rotate in unison and therefore the roof cannot tipeven though loads or forces are applied to it at one One advantage of myinvention is that the en tire guiding arangement is completely outsidethe tank where its operation may be observed and Chi- November 28, 1941;seri l No. 26,819; 5Cla ims. re ns-17c") p H y is filled with a sealingliquid-l 4 which; for exa'inple, may be water in warm climates or brinein colder ones. The roof I2 is provided at its periphery with adepending flange l2a having its 'loweredge immersed in the liquid I4,thus providing a liquid seal between the shell and the roof. I

The outer edge of the roof I2 is provided with" a peripheral extensionl2b carrying an outer de-' pending flange 12c. The members 121) and Iform a weather-hood or protecting means for the trough l3 and preventthe entrance of undesirable foreignmatter into said trough.

For the purpose of guiding the roof in its vertical movements andpreventing it from tipping, I provide a plurality of rocker. arms l5having their lower ends pivoted at [6 to the brackets H on the shell l0and their upper ends pivoted to the members l8 carried by the angle-ironIS on the lower edge of the dependingflange l2cof v the weatherhood.

where any necessary adjustments or repairs can be made without takingthe tank out of service. Another advantage is that the action of" therocker arm guides is not materially affected by ice or snow. Theyhavesuch great leverage that any resistance caused by an accumulation ofice or snow on the flexible joints at the ends of the arms is readilyovercome;

Another feature of theinvention'is that the rocker arms operate with aminimum of friction to the movement It is to be noted also that therocker arms can be easily installed so that erection costs are reducedas compared with other systems.

Other features and advantages of my invention will appear more fully asIproceed with my" specification. I v I;

, In that form of device embodying the features of my invention shown inthe accompanying drawings, Fig. 1? is a view in sideelevationrgrig.

2 is a topplan view with a portion of the. oof

broken away; Fig. 3 is a vertical sectionalview taken as indicated bythe line-3.3 of Fig. 4; and Fig. 4 is a view on an enlarged scaleshowing action of the guiding arrangement. I p

As shown in the drawings, l0 indicates acylindrical tank'or shell withthe bottom H, and I2 a vertically movable roof therefor.

I 3 indicates a trough around the top of the shell which may be eitheron the outside as here shown or on the inside (not shown) The trough theu The upper ends of thepivot arms l5 are provided with rollers 20engaging the outer surface of the trough-l 3 to center the roof andassist in holding it in proper position.

As the roof'rises and falls the arms l5 rock,

as shown in Fig. l, in unison and thus prevent the roof from tipping. Itwill be seen that the rocking of the arms also gives the roof a rotarymotion in its vertical movements.

The upper ends of the arms l5 are pivoted to the members l8 on the pivotpins 18a. 16a indicates the pivot pins for the lower ends of the arms.There is enough lost motion in both the upperand lower pivots to permitthe slight twisting of the arms I5 caused by the rotary motion of theroof in its vertical movements.

Although I have shown a liquid seal between the tank and the roof it isobvious that this'seal may be ,made in other forms. For example, a wipertype seal couldbe used. In each case it will be seen that the sealremains effective as the roof moves vertically. Such a seal therefore,in generahmay be referred to as a flexible seal.

While I have shown and described certain embodiments of my'invention, itis to be under--- stood that it is capable of many modifications.

Changes, therefore, in the construction and arrangement may be madewithout departing from the spirit and scopeof the invention as disclosedin the appended claims, in which it is my intention toclaim all noveltyinherent in my invention as broadly as'permissible, in view of the priorart. I s

What I claim as new, and desire tosecure by Letters Patent, is:

1. A mechanism for holding the movable cover of a stationary verticalcylindrical type fluid storage container to its normal path of motionwith respect to the container as the volume of stored fluid changes,comprising a plurality of at least three spaced links of substantiallength distributed a'rburfd said 'c'oi'rer' a substantial distance fromits center; each link having one end pivoted to the cover and the otherend pivoted to a fixed part of the apparatus, each link being mounted atan angle of about 90 to a radiu'lilf said cover, and all of said linksbeing mounted at the same angle with resQect-to a horizontal plane asdetermined in one direction around the cover and in the samerelationship with respect to said cover, whereby said cover is aasea wrb tate with respect to said containerwhen the cover' moves up and down.

which a liquid seal is provided betweenthe con taifi'r and the cover,including a trough on the container, and means are provided on the coverprotecting": s'ai'dtrough against entry of foreign matter mermaid;

DONALD E. LARSON.

